The Design-Build Model: It’s Still a Thing

Under the design-build model, one entity performs the architecture, engineering and construction components of a project all under a single contract. The concept is nothing new. In fact, it’s been about 20 years since the Construction Industry Institute (CII) teamed up with Penn State University to produce A Comparison of United States Project Delivery Systems, a research study showing that design-build delivery is generally more efficient than traditional construction models.

These results hardly spelled doom for the conventional design-bid-build approach. But a new CII study shows yet again that design-build is “still a thing,” and contractors should recognize its effectiveness and relevance to the industry.

Looking at the latest

For this latest study, CII was joined by the Charles Pankow Foundation, the University of Colorado–Boulder and the University of Florida to create Revisiting Project Delivery Performance, 1998–2018. To gather data, the study looked at 212 construction projects:

The projects studied were of many different types — including simple and complex office, light and heavy industrial, and multistory dwelling.

As was the case with the first CII study, many of the results looked favorably on design-build. For example, construction speed was 36% faster on design-build projects than on design-bid-build jobs. And overall delivery speed was even more remarkable — design-build was 102% faster than the traditionally modeled projects and 61% faster than construction management at-risk.

Another example: Costs for design-build jobs grew at notably lesser rates than for other construction models studied. Specifically, design-build projects averaged 3.8% less cost growth than a project using design-bid-build, and 2.4% less than a job using the construction management at-risk model.

Working together

So, what makes design-build such an effective delivery model in many instances? Proponents say the approach allows the design-build team to deliver a project on accelerated schedules and at lower costs than the design-bid-build model. One reason why is that there’s less “back and forth” between the job’s architects or engineers and its builders. And because no bidding is involved, no time is lost to this process.

In addition, because the designer and contractor are working together, change orders because of errors and omissions, ambiguities, and inconsistencies are greatly reduced — if not eliminated. This isn’t to say that disputes between the design and build factions of a project won’t occur, but they’re often easier to resolve with one team as opposed to two.

Building green

One reason design-build may continue gaining ground is that it’s often a good complement to “green building.” Design-build teams can create a design based on environmentally friendly components rather than trying to work them in later, when work is in progress.

Of course, under the traditional design-bid-build model, an architect could still do this. But design-build often eliminates many of the time-consuming conflicts over precisely which environmentally friendly components to use.

Recognizing risks

To be clear, design-build may not be the right model for every project. It has potential shortcomings. One risk of having designers and builders on the same team is that fewer, if any, checks and balances exist. For instance, an independent design firm may be more likely to catch deviations — inadvertent or otherwise — from the stated plans.

Alternatively, builders not directly related to the design team may be more adamant about sticking to the original design, whereas design-build teams may be at greater risk for constant tinkering with the plans, which can slow down progress and increase costs.

Growing trend

If your construction company has yet to participate in a design-build project, that could change in the not-too-distant future. An interesting finding by FMI Corporation in its 2018 Design-Build Utilization report is that design-build spending is projected to grow 18% overall by 2021. You might particularly look for it in infrastructure jobs, such as highway/street construction and water/wastewater construction.

Again, none of this is to say that the traditional approach to construction is going away anytime soon. But, as you’re no doubt aware, it’s important for contractors to be ready for anything.